Acyl derivatives of azo dyestuffs and process of producing same



Patented Nov. 26, 1940 UNITED STATES PATENT OFFICE ACYL DERIVATIVES OFAZO DYESTUFFS AND PROCESS OF PRODUCING SAME No Drawing. Application June30, 1939, Serial No. 282,326. In Switzerland July 2, 1938 2 Claims.

It has been described in application Serial No. 92,244, filed July 23,1936, that water-insoluble azo dyestuiTs which contain hydroxyl groups,but are free from carboxyl groups and sulfonic groups, can be convertedinto water-soluble preparations by treating them in the presence of atertiary base such as pyridine with acylating agents selected from thegroup consisting of halides of organic acids which contain more than onesalt-forming group selected itself from the group consisting of carboxylgroups and sulfonic groups. Products of this kind have been cited ingreat number in the above mentioned application Serial No. 92,244, filedJuly 23, 1936, for instance the chlorides or bromides of sulfobenzoicacids, of benzene disulfonic acid, of sulfonaphthoic acids, offurane-sulfocarboxylic acid, of sulfoacetic acid and the like.

The ester-like derivatives of dyestuffs thus obtained are characterized,on the one hand, by their solubility in water and, on the other hand, bythe valuable property of regenerating the parent dyestufi under theinfluence of mild saponifying agents. This property renders them veryvaluable for producing fast dyeings, especially for producing fastprints on various substances.

It has now been found that particularly valuable preparations of thekind described above can be obtained by acidylating according to theprocess of application Serial No. 92,244, filed July 23, 1936, thosewater-insoluble azo dyestuffs which are formed by causing diazotizedurethanes of the general formula wherein an stands for alkyl, 1; and astand for members of the group consisting of hydrogen, halogen, CH3 andalkoxy, which urethanes may be produced according to the data of U. S.A. Patents Nos. 2,026,618 and 2,026,619, to react with arylamides ofaromatic ortho-hydroxy-carboxylic acids which couple in ortho-positionto the hydroxyl group, particularly arylamides from the2:3-hydroxy-naphthoic acid and primary amines of the benzene and of thenaphthalene series. Such dyestuffs have been cited in great number in U.S. A. Patent No. 2,040,473, further in British Patents Nos. 459,894 and453,513, in German Patent No. 653,116 and in French Patent No. 801,899.For simplicitys sake reference is 5 made to these patents.

The new products are acyl derivatives of the azo dyestuffs of thegeneral formula are replaced by the acyl radical of a sulfocarboxylicacid, which acyl radicals are united to the azo dyestufi' radical bytheir ("3 groups which acyl derivatives of azo dyestuils in the form oftheir alkali salts are dark powders, soluble in water to red-brown tobrown solutions from which the insoluble dyestufi of the formula Ill OHis precipitated by heating with alkalies.

These products have the advantage over the comparable ester-likeproducts from dyestuifs obtained from diazctizedl-amino-l-benzoylaminoor 4-phenoxyacetylamino-benzenes citedcharacteristic properties of the new acylation products:

Diazotizing component Color of the aqueous solution of gfi g Couplingcomponent Acylating agent tshaetsgghtilllnei saponified acylafion on thefiber product 1 p-Ohloranilide of the 2:3- Ohllltiiride of tlebenzoie-3- Brown Blue.

s onic aci 2 ZY1iS QfiY1J EQ Z?-i t Blmfild? oi tge benzoic-B- do Do.

su 0111C aci 3 ol ii b f i lfe g -hy- Dilcllilloride oighebenzoic-B--.do Do.

s omc aci dmxy naphthom acid. Chloride of the furane suldo. Violet.

4 iocarboxylic acid.

5 fl-Naphthylamide of the 2:3- Chloride of the benzo1c-3- do Do.

hydroxy-naphthoic acid. sulfonic acid.

6 Anilide of the 2:3-hydroxy- Red-brown Bordeaux.

naphthoic acid.

7 do do Garnet.

8 do do Red.

9 do do Bordeaux.

10 v .do Brown Currant. 11 a-Naphthylamide oi the 2:3- Benzoylehoride-Sfi-disuldo Blue.

h hth d. onic aci I 12 Ami a? 5)? 1 2 13 2:3-i 1 ;d r xy- Benzoicac1d-3z5-d1sulfodo Green.

anthracenecarboxylicacid. chloride. 13 g g g d., do Black.

-nap 0-031 3Z0 8- -C8.Y- I] an 2: 2 5 boxylic acid. 14 Anilide of the2:3-hydroxy {a;=O4Hn }Chlor1de of the benzoic-3- .do Blue. 15 naphthoicacid. 0 H suliomc acid. D

Z 5 11 "{1 and 2:00

in application Serial No. 92,244, filed July 23, 1936, that they arebetter suited for producing prints on vegetable fibers or on fibersconsistin of natural or regenerated cellulose.

The following example illustrates the invention, without howeverlimiting the same:

27.1 parts of the product obtained by coupling diazotized 1-amino-25-diethoXy-4-aminocarbethoXy-benzene with 2:3 hydroxy-naphthoic acidanilide are stirred with 150 parts of pyridine at 50-55 C. 33 parts ofthe melted benzoylchloride-meta-sulfonic acid or of the 3-sulfochlorideof the benzoic acid are poured into this solution while allowing thetemperature to rise. Stirring is then continued for some time at C. Assoon as a clear brown solution is obtained of which a sample is clearlysoluble in water, the mixture is cooled to 50 C. and a part of thepyridine is distilled in a vacuum. The residue is dissolved in warmwater, the remaining pyridine is united with acid, for example aqueoushydrochloric acid, and the condensation product is salted out, forinstance with sodium chloride. It is then filtered and the residue iswashed with an aqueous sodium chloride solution as free from pyridinesalts as possible. The pyridine salts may also be removed by dissolvingthe residue once or twice in water and reprecipitating it with sodiumchloride solution. After drying there is obtained a dark colored powderwhich dissolves in water to a brown solution. The parent pigment may beeasily regenerated after addition of substances having an alkaline WhatI claim is: 1. The acyl derivatives of the azo dyestuffs of the generalformula wherein t stands for the radical of a primary aromatic amineselectedfrom the group consisting of aromatic amines of the benzene andof the naphthalene series, in which the hydrogen atom of the OH-groupand at least one of the hydrogen atoms of the two Ngroups which acylderivatives of azo dyestuiis in the form of their alkali salts are darkpowders, soluble in water to brown solutions from which the insolubledyestuff of the formula is precipitated by heating with causticalkalies.

2. Process for the manufacture of derivatives of dyestuffs containing atleast one hydroxyl group, comprising causing dyestuffs free fromcarboxyl groups and from sulfonic groups obtained from diazotizedurethanes of the general formula and arylides from 2:3-hydroxynaphthoicacid and primary aromatic amines selected from the group consisting ofaromatic amines of the benzene and of the naphthalene series, to reactin presence of pyridine with a chloride of a sulfobenzoic acid.

FRANZ ACKERMAN N

